In a large bowl, combine potatoes, onions, green chili, spinach, coriander leaves, chickpea flour, dried methi leaves, cumin seeds, coriander seeds, red chili flakes, red chili powder, and salt. Mix well.
Gradually add water to form a thick batter. Avoid adding too much water, the mixture should not be runny (watch the video above).
Heat oil in a deep pan over medium flame. Drop spoonfuls of the mixture into the hot oil and fry until golden brown and crispy.